Physical activity and exercise are very important parts of a healthy life style. They play an important role in the prevention of chronic non-infectious diseases, but in order to obtain their full benefits; exercise needs to be done on a regular basis (daily) in 30 minutes minimum intervals in two or three sessions during a long period of time. It is important that physical activity regarded and handled as a tool, be prescribed and supervised by qualified physicians with the proper training and expertise. The benefits achieved by regular exercise are evident in quantitative studies outlined in the paper. In USA, the government has included regular exercise in its public health policy, endorsing the importance of physical conditioning and a healthy life style.